This invention is generally directed to imaging members, and more specifically, there is disclosed layered photoconductive imaging members comprised of perinone/perylene dimers, such as alkylimido-monobenzamidazole-perinone-perylene dimers. Photoconductive imaging members containing the aforementioned dimers possess in embodiments a number of advantages as indicated herein, inclusive of being sensitive to blue wavelengths of, for example, about 400 nanometers. The photogenerating layer, which can be exposed to light of the appropriate blue wavelengths simultaneously, or sequentially exhibits, for example, excellent cyclic stability, independent layer discharge, acceptable dark decay characteristics, permits tuning of the electrical properties of the imaging member, and enables substantially no adverse changes in performance over extended time periods. Processes of imaging, especially xerographic imaging and printing, including digital are also encompassed by the present invention.
More specifically, the layered photoconductive imaging members illustrated herein can be selected for a number of different known imaging and printing processes including, for example, multicopy/fax devices, electrophotographic imaging processes, especially xerographic imaging and printing processes wherein negatively charged or positively charged images are rendered visible with toner compositions of an appropriate charge polarity. The imaging members as indicated herein are in embodiments sensitive in the wavelength region of, for example, from about 900 to about 300 nanometers, and in particular, from about 350 to about 450 nanometers. Moreover, the imaging members of the present invention in embodiments can be selected for color xerographic imaging applications where several color printings can be achieved in a single pass.
Layered photoresponsive imaging members have been described in a number of U.S. patents, such as U.S. Pat. No. 4,265,990, the disclosure of which is totally incorporated herein by reference, wherein there is illustrated an imaging member comprised of a photogenerating layer, and an aryl amine hole transport layer. Examples of photogenerating layer components include trigonal selenium, metal phthalocyanines, vanadyl phthalocyanines, and metal free phthalocyanines. Additionally, there is described in U.S. Pat. No. 3,121,006, the disclosure of which is totally incorporated herein by reference, a composite xerographic photoconductive member comprised of finely divided particles of a photoconductive inorganic compound dispersed in an electrically insulating organic resin binder. The binder materials disclosed in the xe2x80x2006 patent comprise a material which is incapable of transporting for any significant distance injected charge carriers generated by the photoconductive particles.
The use of certain perylene pigments as photoconductive substances is also known. There is thus disclosed in Hoechst European Pat. No. Publication 0040402, DE3019326, the use of N,Nxe2x80x2-disubstituted perylene-3,4,9,10-tetracarboxyldiimide pigments as photoconductive substances. Specifically, for example, there is disclosed in this publication N, Nxe2x80x2-bis(3-methoxypropyl)perylene-3,4,9,10-tetracarboxyl-diimide dual layered negatively charged photoreceptors with improved spectral response in the wavelength region of 400 to 700 nanometers. A similar disclosure is presented in Ernst Gunther Schlosser, Journal of Applied Photographic Engineering, Vol. 4, No. 3, page 118 (1978). There are also disclosed in U.S. Pat. No. 3,871,882, the disclosure of which is totally incorporated herein by reference, photoconductive substances comprised of specific perylene-3,4,9,10-tetracarboxylic acid derivative dyestuffs. In accordance with the disclosure of this patent, the photoconductive layer is preferably formed by vapor depositing the dyestuff in a vacuum. Also, there are specifically disclosed in this patent dual layer photoreceptors with perylene-3,4,9,10-tetracarboxylic acid diimide derivatives, which have spectral response in the wavelength region of from 400 to 600 nanometers. Further, in U.S. Pat. No. 4,555,463, the disclosure of which is totally incorporated herein by reference, there is illustrated a layered imaging member with a chloroindium phthalocyanine photogenerating layer. In U.S. Pat. No. 4,587,189, the disclosure of which is totally incorporated herein by reference, there is illustrated a layered imaging member with, for example, a BZP perylene pigment photogenerating component. Both of the aforementioned patents disclose an aryl amine component as a hole transport layer.
Illustrated in U.S. Pat. No. 5,336,577, the disclosure of which is totally incorporated herein by reference, are single layered imaging members.
The appropriate components and processes of the above art patents may be selected for the present invention in embodiments thereof.
It is a feature of the present invention to provide imaging members with many of the advantages illustrated herein.
Another feature disclosed relates to the provision of photoresponsive imaging members with excellent photosensitivity to blue light radiations.
It is yet another feature disclosed that relates to layered photoresponsive imaging members with a sensitivity to blue light, and which members possess in embodiments tunable and preselected electricals, acceptable dark decay characteristics, and high photosensitivity.
Moreover, another feature disclosed relates to the provision of improved layered photoresponsive imaging members comprised of perinone/perylene dimers with photosensitivity to blue light, for example, from about 350 to about 450 nanometers, and wherein blue light is believed to be absorbed by the perinone moiety, and the energy resulting is transferred to or radiated to the perylene chromaphore.
It is yet another feature disclosed wherein there is provided photoconductive imaging members with a photogenerating layer comprised of perinone/perylene dimers photogenerating components, and which layer can be deposited on a supporting substrate.
In further features disclosed there are provided perinone/perylene dimers wherein there is chemically bonded to a perinone blue light sensitive component or chromaphore to a know photogenerator, such as a perylene, and which members exhibited in embodiments increased photosensitivity to blue light as compared to the perinone or perylene alone; and photoresponsive, or photoconductive imaging members which can be selected for imaging processes including color xerography.
Aspects of the present invention relate to a component such as, for example, a photoconductive imaging member comprised of supporting substrate, and thereover a layer comprised of a photogenerator comprised of a perinone/perylene dimer of, for example, alkylimido-monobenzamidazole-perinone-perylenes, bisalkylimido-perinone-perylenes, alkylimido-monobenzamidazole-perylene-perinones or monobenzam idazole-monobenzamidazole-perinone-perylenes of the following general formulas 
wherein R1 is, for example, alkyl with, for example, from 1 to about 25, and more specifically, from 1 to about 10 carbon atoms, inclusive of a substituted or unsubstituted alkyl, branched alkyl with, for example, from 1 to about 26, and more specifically, from 1 to about 12 carbon atoms, cycloalkyl with, for lo example, from 1 to about 25, and more specifically, from 1 to about 10 carbon atoms, or aryl with, for example, from 6 to about 36 carbon atoms, such as phenyl, naphthyl, or a higher polycyclic aromatic exceeding 36 carbon atoms; R2 is, for example, alkyl, a branched alkyl, cycloalkyl, or aryl, such as phenyl, naphthyl, a higher polycyclic aromatic or R1; and R3 is, for example, alkyl, branched alkyl, cycloalkyl, or aryl, such as phenyl, naphthyl, or a higher polycyclic aromatic, such as anthracene or R1; and R1, R2 and R3 can contain a total number of carbons of from 1 and about 50, and more specifically, from 1 to about 12.
Specific examples of perinone/perylene dimers include those of the following formulas 
The perinone/perylene dimers can be prepared by a number of methods, such as the reaction of a naphthalene tetracarboxylic acid and a 1,2-phenylene diamine to form an intermediate product, which may or may not be isolated, and then a further reaction with a monoimido-monoaminoimido perylene in accordance with, for example, the following convergent reaction schemes 
For example, in embodiments monoimido-monoanhydride perylene (1) was prepared according to the processes with minor adaptations thereof as illustrated in Troster, H; Dye and Pigments, 1983, 4, 171-177 and Spietschka, E.; Troster, H.; and U.S. Pat. No. 4,709,029, the disclosure of which is totally incorporated herein by reference, the structure and purity of the perylene which was confirmed primarily using 1H and 13C nuclear magnetic resonance spectroscopy. Monoimido-monoaminoimido perylene (2) was prepared according to U.S. Pat. No. 6,162,571, the disclosure of which is totally incorporated herein by reference, the structure and purity of which was confirmed primarily using 1H and 13C nuclear magnetic resonance spectroscopy. More specifically, a monobenzamidazole monoanhydride perinone can be prepared by placing naphthalene tetracarboxylic acid along with between about 0.1 and about 2 equivalents, or more specifically, between about 1 and about 1.2 equivalents of an appropriately substituted 1,2-phenylene diamine in N,N-dimethylformamide and heating at elevated temperatures. Upon cooling to about room temperature, about 22xc2x0 C. to about 25xc2x0 C., the solid resulting is separated and then dispersed in aqueous potassium hydroxide solution from which the insolubles are filtered and on acidification with concentrated phosphoric acid, heating, isolating and freeze drying provides the desired compound 3.
Monoimide monoanhydride perinone can also be prepared by the dissolution of naphthalene tetracarboxylic acid in an aqueous potassium hydroxide to form a monopotassium salt thereof after buffering with concentrated phosphoric acid. The subsequent addition of from about 1 to about 10 molar equivalents, and more specifically, from about 1 to about 1.2 molar equivalents of a water soluble amine; heating the mixture to up to about 90xc2x0 C., and further acidification of the mixture resulting after heating results in the formation of compound 3xe2x80x2 which can be isolated by hot or cold filtration or other suitable means.
Heating of the above isolated compound 2 and either isolated compounds 3 or 3xe2x80x2 at a temperature of from about 100xc2x0 C. to about 200xc2x0 C. in a suitable solvent results in the formation and isolation on cooling of a perinone-perylene dimmer compound 4xe2x80x2 of the type shown herein but not limited thereto. Compounds of the type 4 or 4xe2x80x2 illustrated herein can be purified by boiling and hot filtering in a suitable solvent such as but not limited to N,N-dimethylformamide.
In embodiments of the present invention there is provided a member wherein the photogenerating layer is of a thickness of from about 5 to about 60 microns; a member wherein the photogenerator component amount is from about 0.05 weight percent to about 30 weight percent with from about 75 weight percent to about 90 weight percent of binder, and wherein the total of the components is about 100 percent; and wherein dimer layer is dispersed in from about 50 weight percent to about 75 weight percent of a polymer binder; a member wherein that absorbs light of a wavelength of from about 375 to about 450 nanometers; an imaging member wherein the supporting substrate is comprised of a conductive substrate comprised of a metal; an imaging member wherein the conductive substrate is aluminum, aluminized polyethylene terephthalate or titanized polyethylene terephthalate; an imaging member wherein the photogenerator binder is selected from the group consisting of polyesters, polyvinyl butyrals, polycarbonates, polystyrene-b-polyvinyl pyridine, and polyvinyl formulas; an imaging member wherein the charge transport is a hole transport of N,Nxe2x80x2-diphenyl-N,N-bis(3-methyl phenyl)-1,1xe2x80x2-biphenyl-4,4xe2x80x2-diamine molecules; a method of imaging which comprises generating an electrostatic latent image on the imaging member of the present invention, developing the latent image, and transferring the developed electrostatic image to a suitable substrate; a method of imaging wherein the imaging member is exposed to light of a wavelength of from about 375 to about 425 nanometers; an imaging apparatus containing a charging component, a development component, a transfer component, and a fixing component and wherein the apparatus contains a photoconductive imaging member comprised of supporting substrate, and thereover a layer comprised of a perinone/perylene photogenerating pigment and a hole transport layer; an imaging member further containing an adhesive layer and a hole blocking layer; an imaging member wherein the blocking layer is contained as a coating on a substrate and wherein the adhesive layer is coated on the blocking layer; an imaging member further containing an adhesive layer and a hole blocking layer; a method of imaging which comprises generating an electrostatic latent image on the imaging member of the present invention, developing the latent image, and transferring the developed electrostatic image to a suitable substrate; and a color method of imaging which comprises generating an electrostatic latent image on the imaging member, developing the latent image, transferring and fixing the developed electrostatic image to a suitable substrate; and photoconductive imaging members with a perinone/perylene dimer, and wherein the perylene is BZP perylene, which BZP is preferably comprised of a mixture of bisbenzimidazo(2,1 -a-i xe2x80x2,2xe2x80x2-b)anthra(2,1,9-def:6,5,10-dxe2x80x2exe2x80x2fxe2x80x2) diisoquinoline-6,11 -dione and bisbenzimidazo(2,1 -a:2xe2x80x2, 1xe2x80x2-a)anthra(2,1,9-def: 6,5,10-dxe2x80x2exe2x80x2fxe2x80x2)diisoquinoline-10,21-dione, reference U.S. Pat. No. 4,587,189, the disclosure of which is totally incorporated herein by reference.
The photogenerating components and the charge transport components are in embodiments dispersed in a suitable binder, such as polycarbonates, polyesters, polyvinylbutaryl, polysiloxanes and polyurethanes. The photogenerating pigments can be present in various amounts, such as, for example, from about 0.05 weight percent to about 30 weight percent and preferably from about 0.05 weight percent to about 5 weight percent and the polymer binder can be present in an amount of from about 25 weight percent to about 75 weight percent. The thickness of this layer can be, for example, from about 5 microns to about 60 microns and preferably from about 1 micron to about 10 microns.
There may also be selected for the members of the present invention a suitable adhesive layer, preferably situated between the substrate and the single layer, examples of adhesives being polyesters, such as VITEL(copyright) PE100 and PE200 available from Goodyear Chemicals, and especially MOR-ESTER 49,0000(copyright) available from Norton Intemational. This adhesive layer can be coated on to the supporting substrate from a suitable solvent, such as tetrahydrofuran and/or dichloromethane solution, to enable a thickness thereof ranging, for example, from about 0.001 to about 5 microns, and more specifically, from about 0.1 to about 3 microns.
The photoconductive imaging members can be economically prepared by a number of methods, such as the coating of the components from a dispersion, and more specifically, as illustrated herein. Thus, the photoresponsive imaging members of the present invention can in embodiments be prepared by a number of known methods, the process parameters being dependent, for example, on the member desired. The photogenerating and charge transport components for the imaging members can be coated as solutions or dispersions onto a selective substrate by the use of a spray coater, dip coater, extrusion coater, roller coater, wire-bar coater, slot coater, doctor blade coater, gravure coater, and the like, and dried at from about 40xc2x0 C. to about 200xc2x0 C. for a suitable period of time, such as from about 10 minutes to about 10 hours under stationary conditions or in an air flow. The coating can be accomplished to provide a final coating thickness of from about 0.01 to about 30 microns after drying. The fabrication conditions for a given photoconductive layer can be tailored to achieve optimum performance and cost in the final members. The coating in embodiments of the present invention can also be accomplished with spray, dip or wire-bar methods such that the final dry thickness of the photogenerating layer is, for example, from about 3 to about 50 microns and preferably from about 5 to about 30 microns after being dried at, for example, about 40xc2x0 C. to about 150xc2x0 C. for about 5 to about 90 minutes.
Examples of substrate layers selected for the imaging members of the present invention can be opaque or substantially transparent, and may comprise any suitable material having the requisite mechanical properties. Thus, the substrate may comprise a layer of insulating material including inorganic or organic polymeric materials, such as MYLAR(copyright) a commercially available polymer, MYLAR(copyright) containing titanium, a layer of an organic or inorganic material having a semiconductive surface layer, such as indium tin oxide, or aluminum arranged thereon, or a conductive material inclusive of aluminum, chromium, nickel, brass or the like. The substrate may be flexible, seamless, or rigid, and may have a number of many different configurations, such as, for example, a plate, a cylindrical drum, a scroll, an endless flexible belt, and the like. In one embodiment, the substrate is in the form of a seamless flexible belt. In some situations, it may be desirable to coat on the back of the substrate, particularly when the substrate is a flexible organic polymeric material, an anticurl layer, such as, for example, polycarbonate materials commercially available as MAKROLON(copyright).
The thickness of the substrate layer depends on many factors, including economical considerations, thus this layer may be of substantial thickness, for example over 3,000 microns, or of a minimum thickness. In one embodiment, the thickness of this layer is from about 75 microns to about 300 microns.
Generally, the thickness of the layer in contact with the supporting substrate depends on a number of factors, including the thicknesses of the substrate, and the amount of components contained in the single layer, and the like. Accordingly, the layer can be of a thickness of, for example, from about 3 microns to about 50 microns, and more specifically, from about 5 microns to about 30 microns. The maximum thickness of the layer in embodiments is dependent primarily upon factors, such as photosensitivity, electrical properties and mechanical considerations. The binder resin present in various suitable amounts, for example from about 5 to about 70, and more specifically, from about 10 to about 50 weight percent, may be selected from a number of known polymers such as poly(vinyl butyral), poly(vinyl carbazole), polyesters, polycarbonates, poly(vinyl chloride), polyacrylates and methacrylates, copolymers of vinyl chloride and vinyl acetate, phenoxy resins, polyurethanes, poly(vinyl alcohol), polyacrylonitrile, polystyrene, and the like. In embodiments of the present invention, it is desirable to select as the single layer coating solvents, such as ketones, alcohols, aromatic hydrocarbons, halogenated aliphatic hydrocarbons, ethers, amines, amides, esters, and the like. Specific examples are cyclohexanone, acetone, methyl ethyl ketone, methanol, ethanol, butanol, amyl alcohol, toluene, xylene, chlorobenzene, carbon tetrachloride, chloroform, methylene chloride, trichloroethylene, tetrahydrofuran, dioxane, diethyl ether, dimethyl formamide, dimethyl acetamide, butyl acetate, ethyl acetate, methoxyethyl acetate, and the like.
As optional adhesives usually in contact with the supporting substrate, there can be selected various known substances inclusive of polyesters as indicated herein, polyamides, poly(vinyl butyral), poly(vinyl alcohol), polyurethane and polyacrylonitrile. This layer is of a suitable thickness, for example a thickness of from about 0.001 micron to about 1 micron. Optionally, this layer may contain effective suitable amounts, for example from about 1 to about 10 weight percent, of conductive and nonconductive particles, such as zinc oxide, titanium dioxide, silicon nitride, carbon black, and the like, to provide, for example, in embodiments of the present invention further desirable electrical and optical properties.
Aryl amines selected for the hole transporting layer in contact with the photogenerating layer include molecules of the following formula 
wherein X is an alkyl group, a halogen, or mixtures thereof, especially those substituents selected from the group consisting of Cl and CH3.
Examples of specific aryl amines are N,Nxe2x80x2-diphenyl-N,Nxe2x80x2-bis (alkylphenyl)-1,1-biphenyl-4,4xe2x80x2-diamine wherein alkyl is selected from the group consisting of methyl, ethyl, propyl, butyl, hexyl, and the like; and N,Nxe2x80x2-diphenyl-N,Nxe2x80x2-bis(halophenyl)-1,1xe2x80x2-biphenyl-4,4xe2x80x2-diamine wherein the halo substituent is preferably a chloro substituent. Other known charge transport molecules can be selected, reference for example U.S. Pat. Nos. 4,921,773 and 4,464,450, the disclosures of which are totally incorporated herein by reference.
Polymer binder examples for the hole transport molecules include components as illustrated, for example, in U.S. Pat. No. 3,121,006, the disclosure of which is totally incorporated herein by reference. Specific examples of polymer binder materials include polycarbonates, acrylate polymers, vinyl polymers, cellulose polymers, polyesters, polysiloxanes, polyamides, polyurethanes and epoxies as well as block, random or alternating copolymers thereof. Preferred electrically inactive binders are comprised of polycarbonate resins with a molecular weight of from about 20,000 to about 100,000 with a molecular weight, preferably Mw of from about 50,000 to about 100,000 being particularly preferred.
Also, included within the scope of the present invention are methods of imaging and printing with the photoresponsive or photoconductive members illustrated herein. These methods generally involve the formation of an electrostatic latent image on the imaging member, followed by developing the image with a toner composition comprised, for example, of thermoplastic resin, colorant, such as pigment, charge additive, and surface additives, reference U.S. Pat. Nos. 4,560,635; 4,298,697 and 4,338,390, the disclosures of which are totally incorporated herein by reference, subsequently transferring the image to a suitable substrate, and permanently affixing, for example, by heat, the image thereto. In those environments wherein the member is to be used in a printing mode, the imaging method is similar with the exception that the exposure step can be accomplished with a laser device or image bar.